Means for checking flame projection from incandescent gas discharge conduits



Nov. 14, 1939. J. MALCZEWSKI MEANS FOR CHECKING FLAME PROJECTION FROMINCANDESCENT GAS DISCHARGE CONDUITS 1mm May 20, 1936 2 Sheets-Sheet, 1

I I JEREMI l NVBQTOR MALCZEWSK l A oRNns Nov. 14,1939. M Z W K]2,179.894 MEANS FOR CHECKING FLAME PROJECTION FROM INCANDESCENT GASDISCHARGE CONDUI'I'S Filed May 20, 1936 2 Sheets-Sheet 2 INVENT'OR JamMALGZEWSKI Patented Nov. 14, 1939 UNITED STATES PATENT OFFiCE CONDUITSJeremi Malczewski, Boulogne-sur-Seine, France,

assignor to Socit Bronzavia, Courbevoie,

(Seine), France, a society of France Application May 20, 1936, SerialNo. 80,890 in Belgium January 6, 1936 15 Claims.

, This invention relates to discharge conduits for incandescent gases orgaseous mixtures, and more particularly, to such conduits havingrelative motion with respect to the surrounding air,

as, for example, exhaust conduits of aircraft or other automotiveengines.

The main purpose of my invention is to improve the construction of suchincandescent gas discharge conduits, in order to eliminate, as far aspossible, the tendency to project flames therefrom.

The principal object of my invention is to provide an incandescent gasdischarge conduit having relative motion with respect to the surroundingair, in which the portion of said discharge conduit comprising the gasoutlet means is swept by the moving air stream, and said gas outletmeans discharge said gas or gases in a direction substantiallyperpendicular to said air stream.

Another object of my invention is to provide an incandescent gasdischarge conduit of the above type, in which said gas outlet meansdischarge said gas or gases progressively and at a substantially uniformvelocity, at all points of 5 said orifice, for the sake of avoiding theconcentration of the flame at any point, and the possibility that saidflame might resist at such point the extinguishing action of the airstream.

A further object of my invention isto provide an incandescent gasdischarge conduit of the above type, in which said gas outlet meansconsist in an orifice "having considerably greater length measured inthe direction of motion of the outflowing gas, than width, measuredperpenw dicularly to said gas flow, and in which said width, preferably,although not necessarily, increases progressively in the direction ofsaid gas how, in order to compensate the drop in gas pressure along saidorifice, and thus to maintain a M substantially uniform discharge ratealong said orifice.

A still further object of my invention is to provide' an incandescentgas discharge conduit as above associated with deflecting bame meanspur- M porting to cause the air stream to sweep directly across theincandescent gas discharge orifice, preferably, although notnecessarily, in a manner to accelerate the air flow abreast of saiddischarge orifice, for example by producing a venturi effect 59 at saidorifice.

A still further object of my invention is to provide, in an internalcombustion engine having relative motion with respect to the surroundingair, exhaust means comprising the improvements 55 herein beforedescribed.

A still further object of my invention is to provide, in an internalcombustion engine as above described, for example of the radial aircrafttype, exhaust means as above defined which overlap circumferentially,thus forming a plurality of ex- 5 haust orifices lying axiallysubstantially in a common cylindrical surface, and associated withdeflecting baffle means, for example a ring type cowl, which purports tocause the air stream to sweep directly across said exhaust orifices,pref- 10 erably, but not exclusively, in a manner to accelerate the airflow abreast of said orifices, for example by producing a venturi effectat said point.

Other objects and advantages will appear to a person skilled in the art,from the following description, with reference to the accompanyingdrawings, which description and drawings are, of course, given mainlyfor the purpose of illustration, and should not be construed as limitingthe scope of my invention.

In these drawings:

Fig. 1 shows, diagrammatically, an end view of a vertical aircraftengine, provided with exhaust means embodying my invention, togetherwith the engine cowling.

Figs. 2 and 3 show, respectively in elevation r and in planecross-section, exhaust means according to my invention.

Figs. 4 and 5 show, also in elevation and in plane cross-section,another form of exhaust means according to the invention.

Fig. 6 shows, in elevation, a radial aircraft engine equipped withexhaust means according to the invention.

Figs. 7 and 8 show, the first in side elevation and the second in frontelevation, an embodiment of the invention, as applied to the exhaust ofa double-row radial aircraft engine, the cylinders of which have beenomitted in Fig. 8, for the sake of simplicity.

In Figs. 1, 2 and 3, I have shown the application of my invention to avertical aircraft engine with cylinders in line. I is the cowl hoodenveloping the engine 4, 2 is the exhaust pipe which passes preferablythrough said cowl and is best disposed perpendicularly to the directionof flow of the air stream. In said exhaust plpaand preferably along thegeneratrix of tangency of said pipe with a plane parallel to said airstream, I provide an elongated slot-like orifice 3', wh ch mayadvantageously be made of relatively narrow width at the end nearest theengine, Where the exhaust gas pressure is highest, and of progressivelyincreasing width, in the direction of. 5

the exhaust gas flow, so as to provide a wider path for the escape ofsaid exhaust gas as the latters pressure drops. The arrow 1 indicatesthe directionof flow of the air stream, which sweeps across the orifice3, and so tends to extinguish the flames.

The exhaust pipe 2 may advantageously be made of ellipticalcross-section, with the longest axis parallel to the air fiow, for thepurpose of reducing the drag; or any other streamlined cross-section maybe used for this purpose. ptionally, the orifice may be provided, asshown in Figs. 4 and 5, on the trailing edge of the ellipse.

Fig. 6 illustrates diagrammatically a radial aircraft engine providedwith exhaust pipes embodying my invention. To this end, I set saidexhaust pipes 2 substantially at right angles to the direction of flowof the air stream and substantially along a circumference tangent to theheads of the engine cylinders 4, and I ,provide each exhaust pipe 2 withan exhaust orifice 3 preferably located along the outermost generatrixof said exhaust pipes, thus discharging the exhaust gases in a directionsubstantially perpendicular to that of the air stream, so that theflames issuing from said exhaust pipe may be almost instantaneouslyextinguished by the air stream.

Figs. 7 and 8 illustrate the application of my invention to an aircraftengine of the double row radial type. The object sought in this designis to arrange the exhaust piping so as to offer, on one hand, theminimum frontal resistance, and, on the other hand, considerableavailable length for the exhaust orifices.

Fig. 7 shows, in side elevation, only one cylinder of each row; whileFig. 8 shows, in front elevation, only the layout of the exhaust piping,the cylinders having been omitted for the sake of simplicity andclearness.

In this embodiment, I arrange the exhaust pipes 2 and 2 from cylinders 4-and 4 respectively, of the front and rear rows of cylinders, so thatsaid exhaust pipes overlap and lie in circles of substantially equaldiameter, lying substantially in a common cylindricalsurface; and Isecure said pipes in place by means of clamps and spacing blocks 6.

I also prefer to locate the exhaust orifices 3 on the outer face of saidexhaust pipes, in the same manner as shown in Fig. 6.

The advantage of this arrangement is that it offers the minimum frontalresistance, for the row of exhaust pipes 2 covers that of the pipes 2furthermore, all the exhaust orifices 3 lie in a cylindrical surface,and it is therefore easy to arrange a cylindrical bafllering 'Ito directthe air stream directly across the mouth of said orifices. 'Said bafllering 1 may readily be associated with an outer cowl v9, and can alsoeasily be designed to accelerate-the air abreast of the orifices, and toincrease thereby its effectiveness in extinguishing the exhaust flames,by designing it to form an annular passage of reduced crosssectionaround said orifices. As shown in Fig. 7, the outlet portions of thepipes 2 and 2 are substantially aligned with the cowl 9, and the onfices 3 project slightly beyond the outer surface of cowl 9. Thus thering formed by the exhaust pipe is to some extent a continuation of thecowl and therefore minimizes the amount of drag while maintaining theadvantages of cooling and flame quenching.

By the means exposed above, I obtain an arrangement of exhaust pipingfor engines having relative motion with respect to the air which has alow drag resistance, and is furthermore remarkably efiiicient inavoiding the projection of flames from. said pipes.

I wish it to be understood, however, that I do not desire to be limitedto the exact constructions described and illustrated, for obviousmodifications thereto will occur to a person skilled in the art. Also myinvention is, of course, applicable to other types of engines, as, forexample, to the V, H and I types.

What I claim is:

1. In a radial aircraft internal combustion engine, exhaust conduitscomprising, in combination, terminal sections lying substantially in acylindrical surface concentric with the engine shaft, and exposed to themoving air stream, each of said terminal sections being substantiallylonger than the arc of said cylindrical surface separating two adjacentcylinders, and overlapping the terminal section of the exhaust conduitof the adjacent cylinder, said terminal sections having dischargeorifices lying in surfaces substantially perpendicularly to the radii ofsaid cylindrical surface.

2. In a radial aircraft internal combustion engine, exhaust conduitscomprising, in combination, terminal sections lying substantially in acylindrical surface concentric with the engine shaft and exposed to themoving air stream, said sections having lateral elongated dischargeoriflees in the sides thereof, said orifices being substantiallycentered on the outermost generatrices of said terminal sections, and abaiile ring associated with said exhaust conduits and forming an annularair passage of relatively small radial width across the mouths of saidelongated discharge orifices.

3. In a double row-radial aircraft internal combustion engine, exhaustconduits comprising, in combination, terminal sections lyingsubstantially in a cylindrical surface concentric with the engine shaftand exposed to the moving air stream, each of said terminal sectionsbeing substantially longer than the arc of said cylindrical surfaceseparating two radially adjacent cylinders, and the terminal section ofthe exhaust conduit from a cylinder in one row overlapping the terminalsection of the exhaust conduit from the adjacent cylinder in the otherrow of cylinders, said terminal sections having "elongated dischargeorifices in the sides thereof, said orifices being, and substantiallycentered, on the outermost generatrices of said terminal sections, and abaille ring associated with said exhaust conduits and forming an annularair passage of relatively small radial width across the mouths of saiddischarge orifices.

4. In a radial aircraft internal combustion engine, exhaust conduitscomprising, in combination, terminal sections lying substantially in acylindrical surface concentric with the engine shaft and exposed to themoving air stream, said sections having lateral elongateddischarge'oriflces in the sides thereof, said orifices beingsubstantially centered on the outermost generatrices "of said terminalsections, and a baflle ring associated with said exhaust conduits andforming,

an annular air passage across the mouths of said discharge orifices,said Lannular passage being of smaller radial width breast of saidelongated discharge orifices than at thejfront entrance to said ringcowl, thus forming an annular venturi having its low pression sectionsubstantially abreast of said discharge orifices.

5. A combustion engine comprising a stationary cylinder having a gasdischarge opening, and

an exhaust conduit secured at one end to the walls of said opening andexposed to a stream of air, said conduit having outlet meanssubstantiallyfiush with the surface of said conduit extending from apoint closely adjacent said opening in said cylinder to a point spaced asubstantial distance therefrom, the axis of said outlet means beingdirected transversely to the direction of flow of said air stream.

6. A combustion engine comprising at least one stationary cylinderhaving a gas discharge opening, and an exhaust conduit secured at oneend to the walls of said opening and exposed to a stream of air, saidconduit having outlet means substantially flush with the lateral wallthereof extending from a point closely adjacent said opening in saidcylinder and parallel to the axis of said conduit, said axis extendingsubstantially vertically to the direction of flow of said air stream.

'7. An internal combustion motor for a vehicle, especially for anaircraft, said motor having radially extending cylinders, an exhaustsystem joined to, said cylinders comprising conduits fixed with respectto said vehicle and exposed to the I action of relative wind, saidconduits extending from said cylinders and terminating in the form of asubstantially continuous ring about the axis of said motor, and outletmeans in said ring causing exhaust gases to escape laterally from saidconduits and longitudinally with said wind.

8. A motor according to claim 7, a cowl surrounding said motor, saidoutlet means being substantially adjacent the outside surface of saidcowling.

9. A motor according to claim 7, an annular cowl surrounding said motor,and said outlet means extending adjacent the outside surface of saidcowl and exhausting said gases outwardly of said cowl.

10. A radial internal combustion motor mounted within a cowling andhaving an exhaust system with at least one exhaust pipe of longitudinalform and flattened section extending substantially parallel to saidcowling. and transversely to the direction of the relative wind, saidpipe having at least a flattened face arranged substantially parallel tothe relative wind and provided with orifice exhaust means.

11. A motor according to claim '7, an annular cowl surrounding saidmotor, said outlet means tinguished by said relative wind.

cowl, and baflle ring means parallel to and spaced from said cowl andconduits for accelerating said wind abreast of said outlet means.

12. A stationary internal combustion engine adapted to be mounted on avehicle and having an exhaust system comprising at least one conduitmeans fixed with respect to said engine and extending from an exhaustport thereof in the path of the relative wind to a point immediatelyadjacent said port and at such a distance from said port to cause theexhausting of incandescent gases, and outlet means flush with a wall ofsaid conduit means disposed in a plane substantially parallel to thedirection of said relative wind and providing an exit of said gases fromsaid conduit means directly into said relative wind as incandescentgases substantially normal to the direction of travel of said gases insaid conduit and thereby extinguishing said gases in the relativestantially right angles to said direction of said wind whereby saidincandescent gases are ex- 14. An engine exhaust'system for an enginehaving at least one fixed cylinder comprising conduit means for leadingincandescent exhaust gases from said engine in a direction transverselyof the direction of the relative wind, and elongated outlet means havingits longitudinal axis perpendicular to the direction of the relativewind for exhausting said gases immediately adjacent said engine directlyas incandescent gases into said relative wind at substantially rightangles to said direction of said wind whereby said incandescent gasesare extinguished by said relative wind. l. i

15. An engine exhaust system as in claim 14, a cowling-for said engine,and said conduit means comprising an exhaust pipe of longitudinal formand flattened section extending substantially parallel to said cowlingand transversely to the direction ofthe relative wind, and saidelongated outlet means extending through a flattened face

